Windows Protection Project

Windows Protection Project



In recent years, damage to windows caused by typhoons becoming larger has occurred frequently. In 2018, due to the typhoon storm 24 that landed in western Japan, the damage alone amounted to about 15,583,000 euros. (Excluding flood damage) It protects windows from strong wind caused by climate change, at the same time reduces energy loss through windows by about 50%, aims at employment of young people and NGOs and creation of social business in promotion. After 6 years of research and development and field test at ESCOT, we succeeded in raising the damage limit by the impact of the window to about 4 times.

It absorbs wind pressure and impact force (F = mv / Δt → F = mv 2 / l) due to collision of scattered material to protect the window glass.

In addition, the adiabatic performance (heat reflux ratio U value = about 3 W / m 2 · K) is twice that of single glass, halving the heat input / output through the window. Specifically, we attach a proprietary bolt to the glass surface on the outside of the window, attach a hollow polycarbonate plate of the same material as bulletproof glass, and fix it with a nut. This will reduce human and physical damage due to cracking of the window glass, while at the same time reducing heat and light expenses = CO2 reduction by improving heat insulation. Promotion and improvement activities are entrusted to young people, NGOs, NPOs, thereby bringing employment and entrepreneurship.

Supplement: How much wind pressure can we withstand? According to Japan’s largest glass maker the wind pressure limit is <48 m / s, about 1290 N> (from Kanto region including Tokyo, AGC company HP) … apparently … Then what was the maximum instantaneous wind speed experienced so far in the Kanto area including Tokyo? The answer was <46.7 m / s>. Will not it be expected that the strong winds exceeding the wind resistance standard will be sufficiently generated if the temperature rise continues in the future?


ESCOT asked a certain glass maker about the effective method to prevent cracking of the window glass from strong winds and scattered materials and it was that there was no effective product except the shutter and the shutter door. However, even in detached houses at present, there are many residences without shutters, and in apartments etc. there are almost no situations. As a glass maker, recommended tempered glass (= glass is fine cracked and hard to get injured by broken fragments) and disaster prevention glass (= made of two glasses and a resin film sandwiched between two glasses) is cracked It was that it was doing. By the way, answers such as “Searching for windows cracking” on the Internet “Maintain film and gum tape on glass surface”, “Close curtain” “Do not place things near Mad” were mainstream.

ESCOT has been spreading through the web for 6 years ago while developing its own <Window guard> which is a window reinforcement product as energy saving, gusts and crime prevention measures, and then improving it. However, crisis consciousness against window cracking was rare in areas other than damaged areas of tornadoes and volcanic eruption, and there was no demand. Also, in apartment houses such as condominiums, the outside of the window was considered as a shared part, and constraints such as agreement of management cooperatives were required. However, after witnessing

the strong wind damage of the large typhoon in 2018, the consciousness to the measures against the window crack increased slightly, but as the question became little by little, the inquiry began to enter.


It is to spread new business based on sustainable innovation that young people, healthy elderly people, NGOs and NPO staff can start with a little start-up fund. Even though it is a depopulated area, there are glass windows where people live, and we are exposed to unexpected high wind risks associated with climate change. Every time a typhoon passes since next year, it is expected that window crack prevention needs will increase. Also, from the viewpoint of CO2 reduction, it is not permissible to leave the energy loss through the window. The purpose of the project is to contribute to the revitalization of a large number of communities by disseminating and developing inexpensive and effective disaster prevention and energy saving technologies in local communities.

※ Source: Ministry of the Environment Global Warming Regional Liaison Committee From eco-windows spread promotion material

Setting all existing houses as “insulated windows” will reduce CO2 emissions by approximately 17 million tons, which is about 23% of the obligation to reduce the Kyoto Protocol.


ESCOT has installed hollow window guards for almost all buildings such as general houses, (detached houses, apartments, condominiums), offices, factories, warehouses and so on. In general households, measures to reduce mold heating due to winter heating cost reduction and dew condensation were mainstream measures. We set up in a company office in the heavy snow area in Yamagata Prefecture for energy saving and crime prevention purpose. There was a food warehouse that stores rice and the like made in Fukushima prefecture as an example in the warehouse. The purpose was to prevent deterioration of packing materials due to ultraviolet light entering through the window. For this reason,

in this warehouse, we shielded the light-shielding film inside all the windows and carried out work with lighting even during the day. So, we installed a hollow window guard in the window, realized the UV cut, used the project, we did not need lighting during the day, succeeded in further protecting the food from strong winds and theft.

At the prefabricated office of the transport company in Tokyo, it improved the effectiveness of air conditioning and heating, protecting the window glass from the stone repelling of the truck and introducing it as noise control measures. In addition, improvement of heat insulation performance of windows at the elderly facilities where tenants live all day brings about great reduction in utility cost throughout the day. We introduced it as a noise countermeasure at a town factory that is concerned with machine noise to the neighborhood. In both cases, the effect on energy saving performance was the purpose of introduction, while window cracking due to typhoons was not assumed. Under these circumstances, the situation has changed since Typhoon No. 24 in September 2018, the situation changed and we decided to introduce the test to the city hall in ESCOT’s local Kashiwa City to verify the effect.

This way, the building that is the object of the project can be said to be a whole building with a window glass in and out. In addition, as for products, there are only three of (1) bolts for window glass, (2) hollow polycarbonate board (local procurement), and (3) silicone used for water leakage repair of bathtub (local procurement). Among them, besides (1), it can be purchased as a commercial item in most countries, such as hardware store. The tool required for construction is available in any place, with only three measures: measure to measure window glass, cutter to cut hollow polycarbonate plate, ice pick to open bolt hole.








Innovation is a thing to say that it is a window crack prevention item that can be attached with <DIY> on the outside of the window, and at the same time it is also an energy saving technology that enhances the thermal insulation of the window.

At least in Japan there was no technique or idea of attaching a protective plate to the outside surface of the windowpane. The <hollow window guard> used in the project has three innovations: <installation place and method>, <wind bolt structure>, <1/3 rule in spreading>. Construction location and method: Place a bolt set on the bolt base on the outer glass surface of the existing window. Next, attach a polycarbonate plate of Hamonica structure derived from shipping buffer material and fasten it from the outside with a nut. Use silicone that is good for water and heat for the adhesive.


Structure of window bolt: There is a protrusion of about 3 mm in the center, making space between glass. In addition, the bonding surface with glass is concave and disperses the impact force outward from the periphery. Since the screw thread is cut in the bolt base, the length can be chosen freely if it is a 3 mm bolt. Although it is necessary to make the length of the bolt within 8 mm in the sliding window, in the FIX window it is also possible to duplex the hollow polycarbonate board by setting longer bolt or attach a thicker hollow polycarbonate board. In addition, it is possible to enhance the impact resistance performance by incorporating cushioning materials such as springs in bolts.

1/3 rule in popularization: Manufacturers, sellers, administrative developers share sales by 1/3. The set price when using a commercial nut is 300 yen. In this case, each one will share 100 yen each. Although the amount of money seems to be small, 2 to 4 sets are required per window, and the number of windows per house is about 30 to 40 in a detached house. I believe that entrepreneurship from the grassroots level opposite to the exclusive sales by large companies is the most important. Other important characteristics of the hollow polycarbonate board are listed below.

















Material properties: 70 times of high strength glass 200 times acrylic, material of aircraft, high speed railroad glass, bulletproof glass, ultra lightweight (about 1 kg / m 2), flame retardant (no flame), super life (20 Years or more)













Light Shape Characteristics:
Light Shielding in the Summer, Light shielding in summer, daylight in winter









Thermal insulation performance: comparable to pair glass (Thermal reflux ratio is about 4 w / m 2 · k)









Soundproof performance: Sound reduction effect of 16 db









UV cut and protect food stock







Easy to removal cleaning



The hollow window guard developed by ESCOT reduces the impact force to the window by about 1/4 and can increase the heat insulation approximately twice. This equipment and construction method was developed jointly with a local town factory. (Patent acquired) Possible damage due to window cracking can be physical damage, human damage, physical damage such as glass, curtains, furniture, home appliances and so on. A newspaper reported that the total damage caused by Typhoon No. 24 stormed from the end of September this year to the beginning of October was 187.3 billion yen (total of insurance companies). When searching examples on the Internet, there was a blog about cracking of windows with strong winds, and there was a statement of damage of 110,000 yen. On the other hand, energy saving effect can be estimated from annual temperature and set temperature of living environment so we will explain it in the next chapter.


Disaster prevention and energy-saving technologies are spread through youths and NGOs. As a goal, we plan to install 10,000 windows of 10,000 houses in the next 5 years. The economic effect and CO2 reduction after implementation will be as follows. The economic effect after 1 year and 2 months amortization period is approximately 1,722,600 euros each year, 3,348 (t – CO 2). In addition, business revenue totaling 2,050,000 euros will be distributed among the manufacturer, seller, administrator. Also, with social disaster prevention effect which is hard to quantify, 10% of the insurance company’s payment due to Typhoon No. 24 storm as described above is attributable to the cracking of the window glass, and if this was prevented beforehand, the damage of about 15,583,000 euros was reduced It becomes a thing.

windstorms are blown off by windstorms, as a result, there are many window glasses and parked cars that suffer great economic damage. If the typhoon accompanying the 24th storm will increase in future, it seems that the glass windows today can be said to be the Achilles tendon in the era of climate change · · ·.


It is important to reproduce with three sets of hard, soft and philosophy. It can be said that domestic reproduction is sufficiently possible from the sales range so far. General purpose goods can be used except bolt base (stainless steel, diameter 3 cm, thickness 0.8 mm) of the mounting bracket which is the center technology of the hollow window guard. Of course, the bolt base can be shipped anywhere in the world if the mail can reach. In addition, multilingualization of project overview and installation manual that describes basic concepts such as 1/3 rule can be done easily.